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          <th colspan="3" align="center">DbEnv::log_stat()</th>
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            <h2 class="title" style="clear: both"><a id="logstat"></a>DbEnv::log_stat()</h2>
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      <pre class="programlisting">#include &lt;db_cxx.h&gt;

int
DbEnv::log_stat(DB_LOG_STAT **statp, u_int32_t flags); </pre>
      <p>
         The <code class="methodname">DbEnv::log_stat()</code> method returns the logging subsystem
         statistics.
    </p>
      <p>
         The <code class="methodname">DbEnv::log_stat()</code> method creates a statistical structure of type
         <code class="literal">DB_LOG_STAT</code> and copies a pointer to it into a user-specified memory
         location.
    </p>
      <p>
         Statistical structures are stored in allocated memory.  If
         application-specific allocation routines have been declared (see
         <a class="xref" href="envset_alloc.html" title="DbEnv::set_alloc()">DbEnv::set_alloc()</a> 
         for more information), they are used to allocate the memory;
         otherwise, the standard C library <span class="bold"><strong>malloc</strong></span>(3) is used.  The caller is responsible
         for deallocating the memory.  To deallocate the memory, free the
         memory reference; references inside the returned memory need not be
         individually freed.
    </p>
      <p>
         The following <code class="literal">DB_LOG_STAT</code> fields will be filled in:
    </p>
      <div class="itemizedlist">
        <ul type="disc">
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_cur_file;</strong></span>
                </p>
            <p>
                        The current log file number.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_cur_offset;</strong></span>
                </p>
            <p>
                        The byte offset in the current log file.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_disk_file;</strong></span>
                </p>
            <p>
                        The log file number of the last record known to be on disk.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_disk_offset;</strong></span>
                </p>
            <p>
                         The byte offset of the last record known to be on disk.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_fileid_init;</strong></span>
                </p>
            <p>
                         The initial allocated file logging identifiers.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_lg_bsize;</strong></span>
                </p>
            <p>
                        The in-memory log record cache size.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_lg_size;</strong></span>
                </p>
            <p>
                        The log file size.
                </p>
          </li>
          <li>
            <p>
                        <span class="bold"><strong>u_int32_t st_magic;</strong></span>
                </p>
            <p>
                        The magic number that identifies a file as a log file.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_maxcommitperflush;</strong></span>
                </p>
            <p>
                         The maximum number of commits contained in a single log flush.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_maxnfileid;</strong></span>
                </p>
            <p>
                         The maximum number of file logging identifiers
                         used.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_mincommitperflush;</strong></span>
                </p>
            <p>
                         The minimum number of commits contained in a single log flush that
                         contained a commit.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>int st_mode;</strong></span>
                </p>
            <p>
                        The mode of any created log files.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_nfileid;</strong></span>
                </p>
            <p>
                        The current number of file logging identifiers.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_rcount;</strong></span>
                </p>
            <p>
                        The number of times the log has been read from disk.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_record;</strong></span>
                </p>
            <p>
                        The number of records written to this log.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>roff_t st_regsize;</strong></span>
                </p>
            <p>
                        The region size, in bytes.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_region_wait;</strong></span>
                </p>
            <p>
                         The number of times that a thread of control was forced to wait before
                         obtaining the log region mutex.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_region_nowait;</strong></span>
                </p>
            <p>
                         The number of times that a thread of control was able to obtain the
                         log region mutex without waiting.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_scount;</strong></span>
                </p>
            <p>
                         The number of times the log has been flushed to disk.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_version;</strong></span>
                </p>
            <p>
                        The version of the log file type.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_w_bytes;</strong></span>
                </p>
            <p>
                         The number of bytes over and above <span class="bold"><strong>st_w_mbytes</strong></span> written to this log.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_w_mbytes;</strong></span>
                </p>
            <p>
                        The number of megabytes written to this log.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_wc_bytes;</strong></span>
                </p>
            <p>
                         The number of bytes over and above <span class="bold"><strong>st_wc_mbytes</strong></span> written to this log since the last
                         checkpoint.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>u_int32_t st_wc_mbytes;</strong></span>
                </p>
            <p>
                         The number of megabytes written to this log since the last checkpoint.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_wcount_fill;</strong></span>
                </p>
            <p>
                         The number of times the log has been written to disk because the
                         in-memory log record cache filled up.
                </p>
          </li>
          <li>
            <p>
                         <span class="bold"><strong>uintmax_t st_wcount;</strong></span>
                </p>
            <p>
                        The number of times the log has been written to disk.
                </p>
          </li>
        </ul>
      </div>
      <p>
              The <code class="methodname">DbEnv::log_stat()</code> method may not be called before the 
              <a class="xref" href="envopen.html" title="DbEnv::open()">DbEnv::open()</a>  method is called.
     </p>
      <p>
         The <code class="methodname">DbEnv::log_stat()</code> <span>
            
            <span>
                method either returns a non-zero error value or throws an
                exception that encapsulates a non-zero error value on
                failure, and returns 0 on success.
            </span>
        </span>
     </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp8416008"></a>Parameters</h3>
            </div>
          </div>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp8379048"></a>statp</h4>
              </div>
            </div>
          </div>
          <p>
                  The <span class="bold"><strong>statp</strong></span> parameter references memory
                  into which a pointer to the allocated statistics structure is copied.
             </p>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp8429784"></a>flags</h4>
              </div>
            </div>
          </div>
          <p>
                  The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
                  or the following value:
             </p>
          <div class="itemizedlist">
            <ul type="disc">
              <li>
                <p><a id="logstat_DB_STAT_CLEAR"></a>
                        <code class="literal">DB_STAT_CLEAR</code>
                    </p>
                <p>
                        Reset statistics after returning their values.
                    </p>
              </li>
            </ul>
          </div>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp8409400"></a>Errors</h3>
            </div>
          </div>
        </div>
        <p>
             The <code class="methodname">DbEnv::log_stat()</code> <span>
            
            <span>
                method may fail and throw a <a class="link" href="dbexception.html" title="Chapter 6. The DbException Class">DbException</a> 
                exception, encapsulating one of the following non-zero errors, or return one
                of the following non-zero errors:
            </span>
        </span>
        </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp8450416"></a>EINVAL</h4>
              </div>
            </div>
          </div>
          <p>
                An invalid flag value or parameter was specified.
            </p>
        </div>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp8449120"></a>Class</h3>
            </div>
          </div>
        </div>
        <p>
                    <a class="link" href="env.html" title="Chapter 5.  The DbEnv Handle">DbEnv</a>, 
                    <a class="link" href="logc.html" title="The DbLogc Handle">DbLogc</a>, 
                    <a class="link" href="lsn.html" title="Chapter 8.  The DbLsn Handle">DbLsn</a> 
            </p>
      </div>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp8451712"></a>See Also</h3>
            </div>
          </div>
        </div>
        <p>
             <a class="xref" href="lsn.html#loglist" title="Logging Subsystem and Related Methods">Logging Subsystem and Related Methods</a> 
        </p>
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